Press brake drive



Feb. 8, 1949. ,B AsTLE 2,461,034

PRES S BRAKE DRIVE Fil ed Aug. 29, 1945 INVENTOR. JAMES B. CASTLE /A r TORNEY Patented Feb. 8, 1 949 4 2,461,034 1 PRESS BRAKE naive James B, Castle, ()aklandgGalif assignorto Re construction. Finance Corporation, San Francisco, Calif., a corporation ofthe United States Application August 29, 1945'; Serial No. 613,345

This invention relates brakes of the heavier type for relatively thick metalv bending and forming generally termed press brakes and the principal'objeot of the present invention is to provide a novel, simple,

efiective hydraulic operating deviceor drive for operating the movable jaw of the brake.

Advantages and special features of the invention willappear inthe following description'and .accompanyingdrawings. I.

In the drawings: I

Fig. 1 is a front view elevation of a conventional press brake fitted with my improved drive or operator.

Fig. 2 is a rear elevation of the press showing the hydraulic power actuating cylinder.

Fig. 3 is a vertical section taken along the line 33 of Fig. 1. v

Fig, 4 is a view similar to that of Fig, 2 but in reducedscale broken centrally along a vertical l andsh w s the u at two P c l n n tea of b tane.v

- Fig. 5 is a detail view showing a modified-form of adjustable connection from the hydraulic cylinder piston to the lever arm of thepress. Fig. dis an end view of Fig. 5. V m

In further detail the drawings show at l the lower front wall or fixed jaw of the brake press, 2 the two vertical side walls, 3 the upper or vertically movable wall or jaw of the press suitably guided as at 4 to move up and down above wall I to force a metal plate against or over any desired form of die supported along the upper edge of fixed wall I, such ,as the special die bar of cross section indicated in position at 5, but which of course may take any form depending .on the nature of the ,bending work being done.

Adjustably secured to slots 6 in wall I is a shelf or table I for supporting the work or plate being bent and which may be fitted with oneor more screw clamps 8 for holding the work to the table. Bolts 9 serve for holding the table at any desired height, and open gaps H1 in the side walls 2 provide for long plates or bars being worked on which extend beyond the side walls 2 of the press. Preferably, suitable floor strips 48 are welded to the lower ends of side plates 2.

Extending between both side walls adjacent the top of the same is a relatively heavy shaft l4 revolvably supported at both ends in bearings l5, while secured to the shaft as by keying or welding are a pair of operating levers l6, l6, one adjacent each side wall}. These levers extend substantially horizontally with their short ends or arms l5 extending forward in overhanging relation to sheet metal bending 2 Claims. (01. 74-110) to the movable press jaw 3 and each pivotally connected thereto as by links I! pivoted at l8 to the lever end and at 19 to a lug 28 welded to the movable jaw 3; It is of course evident that while I show the long operating levers I6 with ithe short levers lfiior'med inone piece, this'is not'neces'sarily so. a

'lihe rear or long ends or arms of the operating levers 16" are provided-with a series of spaced yokes 2|,22', 23', 24 welded along the lower edge of the" lever and each formed witnalignedholes 2s to-selectivelyreceive thebolt'pinllii for piv- *ctauyfponnecun g' to a socket 21 formed on the outer'endof a transversely extending yoke 28 in turn'conne'cted to a piston rod 29 of a hydraulic power cylinder 30;

Piston rodza'extends through a suitable stuffin'g box 30' and is provided with apiston 3| secured to it within the cylinder. The cylinder is pivotallyrnounted on a pin 32 between a pair of spaced lugs 33 welded to a pair of downwardly diverging platesj'34 which extend horizontally between the side walls} and are welded or other} :wise secured thereto.

It'shouldb'e' noted that in the 'open posi t ionpf the press jaws in Fig. 3 the centers of theyoke holes 2 I -25 all substantially fall on a common are 35 so that whichever yoke is connected to the power piston rod will not materially change the press opening. Also that the lower edge of the long lever arms I6" is curved substantially concentric with are 35.

The hydraulic power piston is indicated as double acting and for the pressure liquid to be alternately forced into and discharged from suitable hose connections 36, 31 at opposite'ends of the cylinder, from a pump or other source of liquid pressure under control of suitable valves for starting, stopping, and reversing the piston all as well-known in the hydraulic press art and not shown herein as forming no part of the invention claimed.

In Fig. 2 the yoke 28 which transmits the piston force to the two press levers is indicated as of thick steel plate rigidly welded to both sockets 21 and is also formed with a socket 28 in which the upper end of the piston rod is rigidly secured as by welding or otherwise.

In the arrangement'shown in Fig. 4 two power cylinders are used instead of the one cylinder shown in Figs. 2 and 3, and they are numbered 40, 4| and their piston rods'29 are individually pivotally connected by pins 26' directly to the ends of press levers l8, and the hydraulic power with aligned holes 25 in its lower legs to receive a pin (as shown in Fig. 4 at 26' for connecting to piston rod 29'), while its upper legs are formed with confrontin edges 46 engaging the'grooves '1 44 for sliding to any position along the lever de-' sired. The bracket is locked at any desired point as by one or more set screws H or any other suitable means.

Other features shown in the drawing, common to such press brakes and not concerned with the present claims, include a removable working edge 3" on the jaw to permit various forms and size ofwork-ing edges to be used are well-known and not concerned with the present invention.

In considering my improved press brake operating apparatus above described, it will be noted that in the construction shown in Fig. 4 one of the power cylinders may be omitted and if shaft 14 is large and rigid enough the operating force will be transmitted from one lever 16 through the shaft 14 to the other sotha-t the pressure exerted throughout the length of the press jaw will be 4 operating apparatus and the manner of its operation, what I claim is:

1. In a press brake havin a frame including a pair of spaced side walls and a vertically movable press jaw extending transversely of the press at the forward edges of said walls, the improvement which comprises an overhead shaftextending across between said Walls and provided with bearing support on said walls, a pair of levers spacedly mounted on said shaft each having a short and a long arm, the short arms extending over said movable jaw, link connections between theshort arms and the movable jaw for raising and'low'ering the jaw as the arms are operated,

the-long arms extending overhead rearwardly of the press, a transversely extending rigid yoke q-pivotally-connected at its ends respectively to uniform, and hence the long end of the lever not 7 Also to be noted is that while I show and Prefer -.the power cylinder to be pivotally mounted on the press structure and the piston rod ,pivotally connected to the press lever, these connections may be reversed as wellas understood in pistoncylinder devices as being the equivalent of the r connections shown.

Having thus described my improved press brake said long arms, an upwardly extending, doubleacifing hydraulic power cylinder positioned at the rear of the press with-a piston rod at its upper :end, said piston rod rigidly secured at itsend to a central point on said yoke, a transversely ex.- tending frame member on the press. structure rigidly connecting its side walls, and means pivotally connecting the lower end of said cylinder to said frame member.

2. In a structure as set out in claim 1, said long -lever arms provided with a plurality of selective pivot connections for said yoke spaced along the arms and arranged substantiallyon an arcstruck from the pivotal axis mounting'of saidpower cylinder. i r v JAMES B. CASTLE.

REFERENCES CITED.

The following references are of file of this patent:

UNITED STATES PATENTS- record in the Date Mugford Apr. 16, 1940 

